Bevel-square



(No Model.)

C. A. CARLSON.

BEVBL SQUARE.

Patented June 18, 1895.

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UNITED STATES PATENT Ormesi CARL A. CARLSON, OF ORANGE, MASSACHUSETTS.

BEVEL-SQUARE.

FEGIFICATION forming part of Letters Patent No. 541,151, dated une 18, 1895.

Application iiled April 1, 1895. Serial No. 543,931. (No model.)

To cir/ZZ whom, it may concern:

Be it known that I, CARL A. CARLSON, acitizen of Sweden, and a resident of Orange, in the county of Franklin and State of Massachusetts, have invented new and useful Im' provements in Bevel-Squares, of which the following, taken in connection with the accompanying drawings, is a specification.

This invention relates to an improved bevel square for the purpose of measuring angles ot' any degree such as right, obtuse or acute angles and it is carried out as follows, reference being had to the accompanying drawings, wherein- Figure l represents a side elevation of the instrument. Fig. 2 represents an end view seen from X in Fig. 1. Fig. 3 represents a vertical section on the line 3 3, shown in Fig. l. Fig. 4 represents a vertical section on the line 4 4 shown in Fig. 2; and Fig. 5 represents a detail sectional view on the line 5 5, shown in Fig. l.

Similar letters refer to similar parts whereever they occur on the different parts of the drawings.

The device consists of a pair of metal frames or blade holders A, A, secured together by suitable fastening screws B, B, or equivalent fastening devices as shown.

In the upper ends of the holders A are pivoted to their insides at C, C, Fig. 3, the rotary blade carrying disks D,D, each one of which has a segmental gear surface d in the teeth of which meshes the gear pinion E secured to a spindle e journaled in a suitable bearing in the holders and provided with a serrated head E', by means of which said pinion E, may be turned.

Each blade carrying disk D is provided with a dovetailed shaped rib D', adapted to receive the blade F, provided for this purpose with a correspondingly shaped dovetailed groove f as shown.

G, G, are binder screws, screwed through the frames A, A, against the outsides of the rotary disks D, D, for the purpose of holding their segmental gears d, cl, properly interlocked with the teeth of the pinion E, as shown in Fig. 3.

It will thus be seen that the angles between the blades F, F, and the sides of the holders A, A, may be adjusted'to a nicety simply by turning the serrated head E more or less in either direction, namely, to the right or left, as circumstances may require.

Sometimes both blades F are used, and at other times only one maybe used and its fellow removed according to the nature ot' the angle that is to be measured or laid out by means of the instrument.

Each holder A has a curved slot H through which passes loosely a set screw I that is screwed through a screw threaded perforation in the disk D, and is adapted to bear against the blade F as shown in Figs. 3 and 5. Such set screws I, I, serve to secure the blades F, F, to the disks D, D, and frames A, A, after said disks have been adjusted relative to the angle to be measured or laid out.

t', z', are thumb pieces or serrated heads on the outer ends of the set screws I, I, and I', I', represent thumb nuts on said screws I, I, for the purpose of securing the screws I, I, to the frames A, A, after the blade or blades F have been adjusted in position relative to the said frames A, A.,

'A Through the middle portion of the frames A, A, is made a groove K having a dovetailed miter guide K adaptedto receive the dovetailed groove f of the blade F whenever it is desired to attach `one of the said blades F to the frames A, A, at an angle of forty-five degrees to the latter as shown in Figs. Sand 4:.

K" is a set screw going through the middle portion of one of the frames A for the purpose of attaching the blade F to such frame when laying out or measuring angles of forty-ve degrees.

In the lowerrend of the frames A, A, is made a groove L having a dovetailed projection L adapted to receive the dovetailed groove f on the blade F whenever it is desired to permanently secure the latter at a right angle to the frames A, A, as shown at the lower ends of Figs. 2, 3 and 4:.

L is a set screw for securing the blade F in the groove L, after the blade has been inserted therein.

In practice I prefer to affix a spirit level IWI to one side of the frames A, A, as shown in Figs. 2 and 4f.

In using the device the blades (one or two F are connected to the dovetailed guide ribs D on the rotary disks D and the latter turned by manipulating the thumb piece E as here-V inabove mentioned until the bladeor blades are swung to the desired angle relative to the sides of the frames A, A, after which the blades and disks are secured to the frames by means of the set screws or binder screwsI and their check nuts l as hereinabove mentioned.

For measuring or laying out miters, that is, angles of forty-five degrees, I insert the blade in the miter groove K and secure it in such position by the screw K.

Whenever it is desired to use the device as a true square one of the blades F is inserted in the lower groove Land secured by means of the set screw L as heretofore setforth and described.

Having thus fully described the nature, construction, and operation of my invention, I wish to secure by Letters Patent and claim 1. The herein described bevel square consisting of the frameA having rotary disks D, D, journaled therein and having segmental gears d, d, intermeshing with an adjustable pinion E and longitudinally dove tailed blades F, F, adapted to be secured to said disks and means for securing said blades to their disks after beingr adjusted substantially as and for two subscribing witnesses, on this 28th day*` of March, A. D. 1895.

CARL A. CARLSON.` Witnesses FRANK CoRLssAN, ANDREW NEWMAN. 

